Norwegians are voting in a general election which seems set to go right down to the wire.

The country's two main political alliances have dominated the campaign, but smaller parties could still swing the result.

Who is taking part?

The outgoing government, a centre-right minority coalition, is led by Prime Minister Kjell Magne Bondevik, and controls 62 of the 165 seats in the Norwegian parliament, the Stortinget.

The coalition is made up of three parties - Mr Bondevik's Christian People's Party, the Conservatives and the Liberals - and has also relied on the support of the far-right Progress Party, which has 24 MPs.

The main opposition parties are Labour, the Socialist Party of the Left and the Centre Party. They hold a total of 76 seats.

Outside of the two main blocs, three other MPs sit in parliament.

One represents the Coastal Party, a small pro-whaling party based in the north of the country and firmly opposed to membership of the European Union. The two remaining MPs are independents.

The Marxist Red Electoral Alliance is also tipped to feature in the next parliament.

Who is likely to become prime minister?

Mr Bondevik, an ordained priest, is coming to the end of his second term as prime minister, having previously served between 1997 and 1999.

His main rival is Jens Stoltenberg, the leader of the Labour Party, who led the government for an 18-month spell in between Mr Bondevik's two terms.

Opposition leader Jens Stoltenberg has prime ministerial experience

Progress Party leader Carl I. Hagen has said he will no longer support Mr Bondevik as prime minister, while the centre-right may choose to back Conservative leader Erna Solberg instead.

An opinion poll conducted by MMI and published in the Dagbladet newspaper in early September suggested 38% of voters see Mr Stoltenberg as the best choice for prime minister, followed by Ms Solberg on 12% and Mr Bondevik two further points behind.

Education, care for the elderly and the state of the economy are seen as key campaign issues. The government has promised to introduce more tax breaks while the opposition is planning to spend more on welfare.

Foreign policy appears to be playing less of a role. Norway rejected the offer of EU membership in 1972 and 1994, and the mainstream parties have agreed to suspend further discussions on the subject until after the election.

However, there is widespread agreement that the country should remain a member of Nato.

The Progress Party has devoted much of its attention to immigration policy, and has drawn criticism for some of its campaign material.

What do the opinion polls say?

There will be 169 deputies in the next parliament, elected by proportional representation from 19 electoral districts - the 19 counties of Norway.

An opinion poll commissioned by the leading daily Aftenposten in the last week of the campaign suggests that, backed by the Progress Party, the centre-right coalition will win 84 seats in parliament, one short of an outright majority.

The poll gives the Labour-led opposition alliance 82 seats, while the Coastal Party would win two seats and the Red Election Alliance one.

This means Norway's smaller parties may well hold the balance of power.

Why is the election being held now ?

The current government's mandate has expired.

Under Norwegian law, a general election must be held on a Monday in September every four years. The last vote was held on 10 September 2001.

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